Question

how do we know that does not involve a variable plz answer me fast ​

Answer 1

Answer:

b,c are your answer

hope this helps you

variable are a,b,c p ,q r etc

if any variable not there it is not linear equation

Answer 2

Answer:

(b) 7×20-5

(c)5(21-7)+7×5

HOPE IT HELPS YOU

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